What Is The Most Common Mileage For Toyota Prius Head Gasket Failure?

We have all heard of it, the dreaded "knock on startup." It is the sound of head gasket failure most likely, and it is every Prius owner's nightmare.

A head gasket failure can lead to very costly repairs or even selling the car. But the generation 3 Prius is still wildly popular, so how do you know if the head gasket could fail. Luckily I have some information for you on that.

When Can A Head Gasket Fail On A Toyota Prius?
The picture here is good information. The source is Mitchell 1 Pro demand. Pro demand is a massive part of the automotive industry and has logged hundreds of thousands of vehicle issues.

It is also an excellent resource for technicians who need to look up repair information, recalls, or specs for a vehicle they are working on.

One of the topics that people frequently ask me is about third-generation Prius head gasket failure. 2010 -2013 Prius and Prius V are notorious for failure, but at what interval?

If you look at the graph, most of the problems start occurring around 100k miles and peak about 170k.

Why Does This Problem Occur?
My research and having worked on so many of these now can tell you that the most common reason for failure is the EGR system plugging up.

It also happens because the engine is all aluminum and the heat cycling over time causes a slight separation between the head and the block.

Keeping your EGR system clean (about every 100k clean the cooler and pipes) can help reduce the possibility of this happening.

If you once again refer to the chart, problems really start taking off around 100k. Think about the wear on the car at this point from new. When the vehicle is new, there is no carbon build-up, and everything is operating as it should.

As time goes on, carbon deposits slow the flow of the EGR system and eventually cause a complete block off.

Conclusion
If you think of getting a used 3rd Generation Prius with 100k or more, please do yourself a favor and either clean the system or have it done.

The gen 3 Prius is a good car, but it does have those blasted Achilles heels. Just remember that as you are out on the lot, taking a look. It may even help you negotiate the terms of purchase on the car too.

That is all for today. I look forward to seeing you in the next article. Want to know what I think of a Tesla Model 3? Check it out here.

Check out this wild new battery tech that Tesla has and why it will forever change the auto industry.

Peter Neilson is an automotive consultant specializing in electric cars and hybrid battery technologies. He holds a Bachelor of Science in Automotive Service Technology from Weber State University. Peter can be reached on Linkedin and you can tweet him at The_hybrid_guy on Twitter. Find his page on Facebook at Certified Auto Consulting. Read more of Peter's stories at Toyota news coverage on Torque News. Search Toyota Prius Torque News for more in depth Prius coverage from our reporters.